An unreleased `diff` mod is being built in the Claude Code repo with a docked pane and pluggable backends.

Commits on September 15 and 16 continue a mods/diff build-out no changelog mentions: a docked diff pane whose hunks scroll under a pinned header, an inline /diff dialog off fullscreen, keyboard walk that stops at first and last file instead of wrapping, and a backend abstraction where the git backend owns its own closing empty row. #94594 defers running git until the built-in panel needs it rather than at session start. Reading the mods/ commits stays weeks ahead of the published changelog.